Building secure login flows and session management in React requires understanding multiple authentication patterns. This skill provides production-ready code examples for JWT, OAuth, cookies, and protected routes.

Zustand state management in React Native has subtle timing behaviors that cause hard-to-debug issues. This skill provides proven patterns to handle synchronous set() calls, avoid stale closures in async operations, and implement reliable store subscriptions.

Writing tests for React Native apps requires understanding of mocking native modules, handling async state, and testing Zustand stores. This skill provides proven patterns and code examples for reliable test suites.

React Native styling differs from web CSS. This skill provides proven patterns for NativeWind, BrandColors, platform-specific styles, and responsive layouts to build consistent cross-platform mobile UI.

Complex multi-step operations in React Native are prone to ordering bugs and untested edge cases. This skill provides patterns for modeling state transitions, implementing validated flow steps, and surfacing flow state to the UI.

React Native apps often suffer from scroll jank, unnecessary re-renders, and slow list performance. This skill provides proven patterns for FlatList optimization, memoization, and state management that eliminate performance bottlenecks.

Silent failures create debugging nightmares. Use logging patterns, error message design, and structured debugging techniques to diagnose production issues fast.

React Native apps require proper navigation architecture for tab bars, modals, and deep linking. This skill provides proven Expo Router patterns for production apps.

Building Expo React Native apps that need native iOS capabilities like camera, push notifications, haptics, and secure storage requires platform-specific patterns. This skill provides ready-to-use code examples for implementing these features correctly with proper permission handling and Expo best practices.

React Native authentication requires careful handling of OAuth flows, secure token storage, and session management. This skill provides battle-tested patterns for implementing login with Google, token storage with SecureStore, protected routes with Expo Router, and backend integration.

Async bugs in React Native apps often work in development but fail under load. This skill provides patterns to detect and fix race conditions, floating promises, and async timing issues in Zustand-based state management.

Zustand's simplicity hides timing complexities that cause subtle bugs. Learn patterns for synchronous set() behavior, stale closure prevention, async actions, and selector optimization to write reliable React state management.

Testing React components requires understanding component rendering, user interactions, and async state management. This skill provides ready-to-use patterns for Jest and React Testing Library that help you write reliable tests for components, stores, hooks, and async operations.

Multi-step React operations with async dependencies are prone to ordering bugs and missing preconditions. This skill provides patterns and checklists for implementing robust state machine patterns in React web and React Native applications.

React applications often suffer from unnecessary re-renders and slow list rendering causing poor user experience. This skill provides expert patterns for memoization, virtualization, code splitting, and performance profiling to build fast, responsive React applications.

Silent failures make debugging impossible. This skill teaches you to write React code with built-in observability through structured logging, contextual error messages, and production-ready debugging patterns.

Async bugs in React often work in development but fail under load. This skill provides battle-tested patterns for floating promises, race conditions, and async timing issues with Zustand and React Query.

Async testing requires specific patterns that differ from synchronous code. This skill provides ready-to-use patterns for pytest-asyncio configuration, async fixtures, mocking async functions, and database test isolation.

SQLModel combines Pydantic and SQLAlchemy, creating confusion about models and schemas. Async SQLAlchemy has different rules than sync. This skill provides tested patterns for eager loading, relationships, sessions, and common database operations.

Pydantic v2 has significant API changes from v1. This skill provides proven patterns for validation, serialization, and schema design to help you migrate and build robust data models.